Well, we just purchased a 2005 VDP and love it so far. Since we just got hit with a cold front, the temps dropped to the teens and I got the 'vehicle too low' and 'air ride fault' warnings. This was two days into ownership and my wife and I were freaking out. We feel better after reading most of the post regarding this issue. I'm going to try the relay first, then the seal for the compressor. If that does not fix the issue then we will order the arnott shocks. Again, this has only happened in the mornings when it's cold outside and the car has been sitting overnight. If the car is given time to warm up the messages go away.

 

I haven't read thru this whole thread but this 'air suspension fault' and 'ride to low' when it gets cold out is very common and happens to my 2006 Super V8 Portfolio as well.
So the question is, why not just get the Arnot coil spring conversion kit and get rid of the air suspension completely?

 

That is a valid question. For my part, I just want something to work right !!!! .... Silly me huh!!!! I think that the cost is a big factor. I like the air ride, especially now that I have found out it can be adjusted electronically. Hopefully, the relay or the compressor seal fixes my issue, if not, then it's the arnotts since everyone who has installed them says that the problem has gone away since changing the OEM shocks.

 

I am not a Jaguar mechanic; however, from the posts by other forum members, the ASF and "too low" warnings are symptoms for a failing compressor. My 2005 XJ8L started giving me the ASF over two years ago (over 40K miles ago) always accompanied with a harsh ride when the temperature would drop below 40F. Yesterday, with temperatures hovering around 10F, I finally got the "too low" warning in addition to the ASF. The front end was noticeably lower than normal. After allowing the car to sit at work for 8 hours, the codes cleared when I started the car and the front rose to the normal height. Fortunately, I had already ordered a replacement compressor from Arnott (total cost $404) so I swapped out the old compressor this morning. It took me about 3 hours, not from the exchange of the compressors which was very straight forward, but from the rusted fasteners for the radiator shield, mud flaps, etc. All the fittings and mounting hardware are included with the new compressor. I should be good for another 117,000 miles (fingers crossed).

 

dear all,

there are many posts and threads about this issue.
as per my own experience and as already posted earlier, replacing compressor is a temporary solution if you have an air leak on the suspension.
air suspension fault message comes when the compressor cannot give enough air in a certain time frame .
if you car is very low every morning, there is another issue than compressor .
for me, i had to change compressor + set of front air shocks and now the message doesn't appear anymore .

thierry

 

Well I do not know what to tell you but I am pretty sure you need new front air shocks because if it would've been the air compressor your vehicle would've been sat on four wheels not just only sitting low in the front you might have a small leak from the air Bags from the shocks and the only reason you are driving now is thanks to the air compressor

 

Good input I am having the same issue I already replaced the rear air shocks with a new pair from Arnott when I went to start my car in the morning and it was sitting low in the rear. Now is sits low in the front but not overnight it does that only when I am in the northern states like Kansas and Wisconsin whe is below 40 degrees it sits low in the front and when I start the car I have to wait for a while to see them up most of the time I lift the front fenders a little but to help the rising but I am not sure if it's the compressor or front air shocks. I read in this forum that if the compressor sends air to the reservoir and shocks and it does it in less than 3 min meaning your suspension rises under 3 min and the relay makes the compressor stop it means that the compressor is good and the issue is a leaking or maybe two air shocks, at this point I do not really know I drive a lot to the northern states and I Live in Florida but in Florida it does not sit low in the front only if it is above 45 degrees.
I also read that if it is a failing compressor the car would sit low on the four wheels rather than in just two.

 

I dont have any low suspension issues. My problem is a harsh ride, sometimes it feels like Im driving over a cattle grid. My Jag garage says no fault codes found. It has previously been mention about a CAT issue,however I dont have any warning messages. I thinking about getting rid and going back to the reliable Spring and shock.

 

Don't forget that the front shocks run at a higher pressure than the rear. If the compressor is worn and not putting out enough pressure, only the fronts would be low. The car has been sitting for over 24 hours now and the front gas not dipped.

 

Hi all
Have not seen on this entire thread any dialogue on the suspension raising by itself. Happened last night and it's pretty extreme. I did disconnect the battery last week as I had to change the center dash clock bulb and in addition to the suspension issue yesterday I have a yellow message with a Parkbrake Fault reading yet I can't feel any issues with the Parkbrake, works fine. Any thoughts from anyone before I take it in?

Thanks

 

I have the same suspension problem ony 04 XJR.

​I have replaced the relay, the battery, shocks and compressor. When I start the car, the suspension fault light shows, and the.compressor does not always come on. Sometimes it just clicks a few times and fails to run. If I leave it turned off for half an hour, it will often come on okay. At other times the headlights will flick on and off, even when switched off, after it does this, it shows a suspension fault.
Any ideas?

 

I don't know if someone has suggested this already but have you renewed the three earth points behind the headlights?
There're are three of them, two on the right, one on the left comprising aluminum studs and even if they look ok they are often the cause of random electrical problems on all sorts of different systems due to corrosion.
Here is a link on another website which details how to deal with the problem;
https://www.jaguarforum.com/showthre...=86334&page=26
Go to post 259
This is a must do job anyway, cause if the earth points are not causing problems yet, they eventually will. Don't be fooled if they look OK.

 

Hi Chris.
thanks very much for your help. I checked the ground points behind the headlights and found one of them finger tight. I nipoed it up and it appears that the problem is completely solved. All the warnings are off and the compressor is running correctly.
Thanks again.
David.
(Born in Belfast, living in USA)

 

Hi David
That's great news.
The earth studs can literally come off in your hands, as one of mine did.
I replaced mine along the lines of the link I provided in my last post. I was suffering from flickering headlights.

 

Hi, I'm trying to figure out which relay to replace to try to fix the AIR SUSPENSION FAULT / VEHICLE TOO LOW in my 2004 XJ8.

Looking at my 2004 Jaguar XJ Electrical Guide, p. 19-20:

I assume "fuse box p/side" means the front power distribution fuse box, not the passenger junction fuse box, which has only 1 relay and isn't under the hood.

The front power distribution fuse box has "R4" in the top row (of 2 rows of relays), farthest right.
But the manual says that R1 (top row, farthest left) is the air suspension relay:



I ordered a (used) FoMoCo 5M5T14B192CA Automotive Relay 4 Prong 12V 40A, which is the R1 relay.
My manual says that R4 is the wiper on/off relay, and my wipers work fine.
When you said R4, did that mean R4 as indicated in the diagram above?
(Note the diagram is upside-down compared to what you'd see looking at it standing in front of the car).



Fusebox as seen from front bumper R4 at far left; R1 at far right

 

I've had everything done to my suspension. Shocks, air compressor, valves, etc. However, my message is on. How can I get the message removed?

 

Does your suspention work fine? (i.e. goes up, does NOT loose hight overnight (or if looses its not more than 2cm)), does ride feel normal?
In my opinion, if all of the above is working fine, than try to clear it with computer diagnostics and ride the car for some KM.

 

Hi I am a new member and this is my first post.

I have just purchased a second hand 2005 xj8 3.6 .with 170k kilometers. It is a beautiful car.

I have read nearly all of this very long thread. I seem to have a problem not covered by it...? if that is possible..

The previous owner installed 4 original new air compressors 6 months ago supplied by sng barrat U.K after the car sank to the floor.
They were not installed by a recognized jaguar dealer shop.
The air suspension warning light comes on after about 15 minutes of driving- not before.
The car is up and there is no problem when driving or no problem with climate temperature.-I live in a moderate climate.
The battery is new and was installed 1 year ago (before installation of new compressors).
The code of the fault that appeared was C2303 . The previous owner said it appeared two weeks after he changed the 4 compressors.
There are NO LEAKS that can be detected . The car stays up and drives beautifully.
The only snag is the damn warning light wont go off..
It would appear to be an electronic computer issue? a relay fuse? an alien?
I would greatly appreciate any advice from the forum.

 

C2303 is Reservoir plausibility. The computer sees the reservoir as not behaving as expected, either not pressurizing as the compressor runs, keeping pressure when the computer is expecting it to vent, or some such condition that does not match what it expects to see given what it's sending out as commands to the system. Looking at the website for SNG Barrat, it appears they supply the same Bilstein struts that were original equipment, so they ought to work just fine, assuming the rest of the system is working. The C2303 is almost always poor compressor performance, meaning the compressor runs without the expected increase in reservoir pressure.

 

Thank You
So I should check with the seller if the compressor was replaced and if not, replace it/fix it?